Tremolo devices for stringed musical instruments are widely known. They are used to simultaneously and significantly either reduce or increase the tension on all strings of the musical instrument, to thereby produce unusual tone variations or vibrato. Examples of tremolos are shown in U.S. Pat. No. 2,741,146 to Fender and in U.S. Pat. No. 4,497,236 to Floyd Rose, one of the inventors named herein.
As used in connection with, for example, an electric guitar having a body, a neck portion and a plurality of strings, each of which is anchored at one end to the neck portion of the guitar and extends rearwardly to and over a portion of the body of the guitar, a typical tremolo device includes a base plate that is pivotally mounted on the guitar body and has string attachment means thereon to which the other ends of the strings are anchored. The strings are anchored to the attachment means at points in a plane above the level of the plane of the base plate, with both planes being generally parallel to the plane of the guitar body. The typical tremolo device also includes a flange member integral with the base plate that extends downwardly into a cavity in the body of the guitar, at approximately a right angle to the base plate. It also includes a plurality of springs connected at one of their ends to the lower end of the flange member and at the other of their ends to a wall of the cavity in the guitar body. The arrangement is such that the tension in the strings and the bias of the springs counterbalance one another when the strings are in tune and the base plate of the tremolo device is stationary at a neutral first position. A tremolo bar that is fixed to the base plate is also provided to allow the user to manually pivot the base plate relative to the guitar body, either toward a second position at which the tension in the strings is reduced and the tone of the guitar shifts in the flat direction, or towards a third position at which the tension in the strings is increased and the tone of the guitar shifts in the sharp direction.
Should one of the strings of the guitar break during a performance being given by a user of the guitar, the balance theretofore existing between the tension in the unbroken strings and the bias of the strings of the tremolo device is disturbed, and the base plate of the tremolo device pivots downwardly under the bias of the springs until the tension in the remaining unbroken strings again counterbalances the bias of the strings. Thus, the individual tensions in the remaining unbroken strings increase and the tones of the strings all shift in the sharp direction, creating a performance problem for the user who must either stop the performance for a sufficient time either to obtain a new guitar or to retune the remaining strings of the guitar in hand, both of which are time consuming procedures.
It is, therefore, a primary object of the present invention to provide an improved tremolo apparatus having provision therein to allow immediate retuning of unbroken strings of a stringed instrument when one of the strings thereof breaks during a performance.
It is another object of the present invention to provide such a tremolo apparatus in which the tremolo base plate can be quickly returned to and held at its original neutral first position following the breakage of a string in the instrument so that the user's performance can be continued with only a minor interruption.
A further object of the present invention is to provide such a tremolo apparatus which, in addition to allowing the tremolo base plate to be returned to its original neutral first position following a string break, allows the tremolo apparatus to continue to be used with respect to shifting the base plate toward its second position, whereat the remaining unbroken strings are shifted in the flat direction.
Further objects and advantages of this invention will become apparent as the following description proceeds.